/****************************************************************************
 *
 * Copyright 2016 Samsung Electronics All Rights Reserved.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 * http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing,
 * software distributed under the License is distributed on an
 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND,
 * either express or implied. See the License for the specific
 * language governing permissions and limitations under the License.
 *
 ****************************************************************************/

/*
 *  RFC 1115/1319 compliant MD2 implementation
 *
 *  Copyright (C) 2006-2015, ARM Limited, All Rights Reserved
 *  SPDX-License-Identifier: Apache-2.0
 *
 *  Licensed under the Apache License, Version 2.0 (the "License"); you may
 *  not use this file except in compliance with the License.
 *  You may obtain a copy of the License at
 *
 *  http://www.apache.org/licenses/LICENSE-2.0
 *
 *  Unless required by applicable law or agreed to in writing, software
 *  distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
 *  WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 *  See the License for the specific language governing permissions and
 *  limitations under the License.
 *
 *  This file is part of mbed TLS (https://tls.mbed.org)
 */
/*
 *  The MD2 algorithm was designed by Ron Rivest in 1989.
 *
 *  http://www.ietf.org/rfc/rfc1115.txt
 *  http://www.ietf.org/rfc/rfc1319.txt
 */

#include "tls/config.h"

#if defined(MBEDTLS_MD2_C)

#include "tls/md2.h"

#include <string.h>

#if defined(MBEDTLS_SELF_TEST)
#if defined(MBEDTLS_PLATFORM_C)
#include "tls/platform.h"
#else
#include <stdio.h>
#define mbedtls_printf printf
#endif							/* MBEDTLS_PLATFORM_C */
#endif							/* MBEDTLS_SELF_TEST */

#if !defined(MBEDTLS_MD2_ALT)

/* Implementation that should never be optimized out by the compiler */
static void mbedtls_zeroize(void *v, size_t n)
{
	volatile unsigned char *p = v;
	while (n--) {
		*p++ = 0;
	}
}

static const unsigned char PI_SUBST[256] = {
	0x29, 0x2E, 0x43, 0xC9, 0xA2, 0xD8, 0x7C, 0x01, 0x3D, 0x36,
	0x54, 0xA1, 0xEC, 0xF0, 0x06, 0x13, 0x62, 0xA7, 0x05, 0xF3,
	0xC0, 0xC7, 0x73, 0x8C, 0x98, 0x93, 0x2B, 0xD9, 0xBC, 0x4C,
	0x82, 0xCA, 0x1E, 0x9B, 0x57, 0x3C, 0xFD, 0xD4, 0xE0, 0x16,
	0x67, 0x42, 0x6F, 0x18, 0x8A, 0x17, 0xE5, 0x12, 0xBE, 0x4E,
	0xC4, 0xD6, 0xDA, 0x9E, 0xDE, 0x49, 0xA0, 0xFB, 0xF5, 0x8E,
	0xBB, 0x2F, 0xEE, 0x7A, 0xA9, 0x68, 0x79, 0x91, 0x15, 0xB2,
	0x07, 0x3F, 0x94, 0xC2, 0x10, 0x89, 0x0B, 0x22, 0x5F, 0x21,
	0x80, 0x7F, 0x5D, 0x9A, 0x5A, 0x90, 0x32, 0x27, 0x35, 0x3E,
	0xCC, 0xE7, 0xBF, 0xF7, 0x97, 0x03, 0xFF, 0x19, 0x30, 0xB3,
	0x48, 0xA5, 0xB5, 0xD1, 0xD7, 0x5E, 0x92, 0x2A, 0xAC, 0x56,
	0xAA, 0xC6, 0x4F, 0xB8, 0x38, 0xD2, 0x96, 0xA4, 0x7D, 0xB6,
	0x76, 0xFC, 0x6B, 0xE2, 0x9C, 0x74, 0x04, 0xF1, 0x45, 0x9D,
	0x70, 0x59, 0x64, 0x71, 0x87, 0x20, 0x86, 0x5B, 0xCF, 0x65,
	0xE6, 0x2D, 0xA8, 0x02, 0x1B, 0x60, 0x25, 0xAD, 0xAE, 0xB0,
	0xB9, 0xF6, 0x1C, 0x46, 0x61, 0x69, 0x34, 0x40, 0x7E, 0x0F,
	0x55, 0x47, 0xA3, 0x23, 0xDD, 0x51, 0xAF, 0x3A, 0xC3, 0x5C,
	0xF9, 0xCE, 0xBA, 0xC5, 0xEA, 0x26, 0x2C, 0x53, 0x0D, 0x6E,
	0x85, 0x28, 0x84, 0x09, 0xD3, 0xDF, 0xCD, 0xF4, 0x41, 0x81,
	0x4D, 0x52, 0x6A, 0xDC, 0x37, 0xC8, 0x6C, 0xC1, 0xAB, 0xFA,
	0x24, 0xE1, 0x7B, 0x08, 0x0C, 0xBD, 0xB1, 0x4A, 0x78, 0x88,
	0x95, 0x8B, 0xE3, 0x63, 0xE8, 0x6D, 0xE9, 0xCB, 0xD5, 0xFE,
	0x3B, 0x00, 0x1D, 0x39, 0xF2, 0xEF, 0xB7, 0x0E, 0x66, 0x58,
	0xD0, 0xE4, 0xA6, 0x77, 0x72, 0xF8, 0xEB, 0x75, 0x4B, 0x0A,
	0x31, 0x44, 0x50, 0xB4, 0x8F, 0xED, 0x1F, 0x1A, 0xDB, 0x99,
	0x8D, 0x33, 0x9F, 0x11, 0x83, 0x14
};

void mbedtls_md2_init(mbedtls_md2_context *ctx)
{
	memset(ctx, 0, sizeof(mbedtls_md2_context));
}

void mbedtls_md2_free(mbedtls_md2_context *ctx)
{
	if (ctx == NULL) {
		return;
	}

	mbedtls_zeroize(ctx, sizeof(mbedtls_md2_context));
}

void mbedtls_md2_clone(mbedtls_md2_context *dst, const mbedtls_md2_context *src)
{
	*dst = *src;
}

/*
 * MD2 context setup
 */
void mbedtls_md2_starts(mbedtls_md2_context *ctx)
{
	memset(ctx->cksum, 0, 16);
	memset(ctx->state, 0, 46);
	memset(ctx->buffer, 0, 16);
	ctx->left = 0;
}

#if !defined(MBEDTLS_MD2_PROCESS_ALT)
void mbedtls_md2_process(mbedtls_md2_context *ctx)
{
	int i, j;
	unsigned char t = 0;

	for (i = 0; i < 16; i++) {
		ctx->state[i + 16] = ctx->buffer[i];
		ctx->state[i + 32] = (unsigned char)(ctx->buffer[i] ^ ctx->state[i]);
	}

	for (i = 0; i < 18; i++) {
		for (j = 0; j < 48; j++) {
			ctx->state[j] = (unsigned char)
							(ctx->state[j] ^ PI_SUBST[t]);
			t = ctx->state[j];
		}

		t = (unsigned char)(t + i);
	}

	t = ctx->cksum[15];

	for (i = 0; i < 16; i++) {
		ctx->cksum[i] = (unsigned char)
						(ctx->cksum[i] ^ PI_SUBST[ctx->buffer[i] ^ t]);
		t = ctx->cksum[i];
	}
}
#endif							/* !MBEDTLS_MD2_PROCESS_ALT */

/*
 * MD2 process buffer
 */
void mbedtls_md2_update(mbedtls_md2_context *ctx, const unsigned char *input, size_t ilen)
{
	size_t fill;

	while (ilen > 0) {
		if (ctx->left + ilen > 16) {
			fill = 16 - ctx->left;
		} else {
			fill = ilen;
		}

		memcpy(ctx->buffer + ctx->left, input, fill);

		ctx->left += fill;
		input += fill;
		ilen -= fill;

		if (ctx->left == 16) {
			ctx->left = 0;
			mbedtls_md2_process(ctx);
		}
	}
}

/*
 * MD2 final digest
 */
void mbedtls_md2_finish(mbedtls_md2_context *ctx, unsigned char output[16])
{
	size_t i;
	unsigned char x;

	x = (unsigned char)(16 - ctx->left);

	for (i = ctx->left; i < 16; i++) {
		ctx->buffer[i] = x;
	}

	mbedtls_md2_process(ctx);

	memcpy(ctx->buffer, ctx->cksum, 16);
	mbedtls_md2_process(ctx);

	memcpy(output, ctx->state, 16);
}

#endif							/* !MBEDTLS_MD2_ALT */

/*
 * output = MD2( input buffer )
 */
void mbedtls_md2(const unsigned char *input, size_t ilen, unsigned char output[16])
{
	mbedtls_md2_context ctx;

	mbedtls_md2_init(&ctx);
	mbedtls_md2_starts(&ctx);
	mbedtls_md2_update(&ctx, input, ilen);
	mbedtls_md2_finish(&ctx, output);
	mbedtls_md2_free(&ctx);
}

#if defined(MBEDTLS_SELF_TEST)

/*
 * RFC 1319 test vectors
 */
static const char md2_test_str[7][81] = {
	{""},
	{"a"},
	{"abc"},
	{"message digest"},
	{"abcdefghijklmnopqrstuvwxyz"},
	{"ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789"},
	{"12345678901234567890123456789012345678901234567890123456789012" "345678901234567890"}
};

static const unsigned char md2_test_sum[7][16] = {
	{
		0x83, 0x50, 0xE5, 0xA3, 0xE2, 0x4C, 0x15, 0x3D,
		0xF2, 0x27, 0x5C, 0x9F, 0x80, 0x69, 0x27, 0x73
	},
	{
		0x32, 0xEC, 0x01, 0xEC, 0x4A, 0x6D, 0xAC, 0x72,
		0xC0, 0xAB, 0x96, 0xFB, 0x34, 0xC0, 0xB5, 0xD1
	},
	{
		0xDA, 0x85, 0x3B, 0x0D, 0x3F, 0x88, 0xD9, 0x9B,
		0x30, 0x28, 0x3A, 0x69, 0xE6, 0xDE, 0xD6, 0xBB
	},
	{
		0xAB, 0x4F, 0x49, 0x6B, 0xFB, 0x2A, 0x53, 0x0B,
		0x21, 0x9F, 0xF3, 0x30, 0x31, 0xFE, 0x06, 0xB0
	},
	{
		0x4E, 0x8D, 0xDF, 0xF3, 0x65, 0x02, 0x92, 0xAB,
		0x5A, 0x41, 0x08, 0xC3, 0xAA, 0x47, 0x94, 0x0B
	},
	{
		0xDA, 0x33, 0xDE, 0xF2, 0xA4, 0x2D, 0xF1, 0x39,
		0x75, 0x35, 0x28, 0x46, 0xC3, 0x03, 0x38, 0xCD
	},
	{
		0xD5, 0x97, 0x6F, 0x79, 0xD8, 0x3D, 0x3A, 0x0D,
		0xC9, 0x80, 0x6C, 0x3C, 0x66, 0xF3, 0xEF, 0xD8
	}
};

/*
 * Checkup routine
 */
int mbedtls_md2_self_test(int verbose)
{
	int i;
	unsigned char md2sum[16];

	for (i = 0; i < 7; i++) {
		if (verbose != 0) {
			mbedtls_printf("  MD2 test #%d: ", i + 1);
		}

		mbedtls_md2((unsigned char *)md2_test_str[i], strlen(md2_test_str[i]), md2sum);

		if (memcmp(md2sum, md2_test_sum[i], 16) != 0) {
			if (verbose != 0) {
				mbedtls_printf("failed\n");
			}

			return (1);
		}

		if (verbose != 0) {
			mbedtls_printf("passed\n");
		}
	}

	if (verbose != 0) {
		mbedtls_printf("\n");
	}

	return (0);
}

#endif							/* MBEDTLS_SELF_TEST */

#endif							/* MBEDTLS_MD2_C */
